Electromagnetic transducers are known for use both in transforming electrical power into mechanical power and transforming mechanical power into electrical power. In both cases, power producing capability results due to relative movement between magnetic elements and electrically conductive elements, as is well known, for example, in the application of this phenomenon to motors, alternators and generators.
While it is well known that motor, alternator and generator devices can be made that are quite light in weight, and while at least some known lightweight devices have been capable of operation at high speeds, such devices have not been capable of operation at high speeds to produce high power. For example, high power density devices of 0.6 horsepower per pound of weight are known for intermittent operation, but such devices are incapable of continuous operation at high power densities in excess of 1.0 horsepower per pound.
Known electromagnetic transducer devices have also not been capable of simultaneous high speed and high torque operation and/or have not provided adequate efficiency in operation. In addition, prior shell construction devices have not used both dispersed conductors and dispersed phase flux carrying means in the armature and have, therefore, also been limited to low speed, which, even at high torque, leads to low power density.
It is also well known that an electromagnetic transducer can include a stator and rotor arrangement, and that such an arrangement can include positioning magnetic elements on the rotor (see, for example, U.S. Pat. Nos. 3,663,850, 3,858,071, and 4,451,749), as well as on the stator (see, for example, U.S. Pat. Nos. 3,102,964, 3,312,846, 3,602,749, 3,729,642 and 4,114,057). It has also been heretofore suggested that a double set of polar pieces could be utilized (see, for example, U.S. Pat. No. 4,517,484).
In addition, a shell type rotor has been heretofore suggested (see, for example, U.S. Pat. Nos. 295,368, 3,845,338 and 4,398,167), and a double shell rotor arrangement has also been suggested (see, for example, U.S. Pat. No. 3,134,037).
It has also been heretofore suggested that a bundle of wires can be utilized in place of a single conductor in the armature assembly of a motor (see, for example, U.S. Pat. Nos. 497,001, 1,227,185, 3,014,139, 3,128,402, 3,538,364 and 4,321,494, as well as British Patent No. 9,557) with such wires being stated to be for high voltage and high current usage and/or to reduce current flow loss, the so-called skin effect, and heating due to eddy currents, and with such wires being utilized in conjunction with solid and/or laminated cores (see, for example, U.S. Pat. Nos. 3,014,139, 3,128,402, and British Patent No. 9,557).
It has also been heretofore suggested than an electromagnetic transducer could have a power to weight ratio of up to about one horsepower to one pound (see, for example, U.S. Pat. No. 3,275,683). In addition, cooling of a motor, to increase power handling capability, using a gas, liquid, or a mixture of a gas and liquid, is well known (see, for example, U.S. Pat. No. 4,128,364).
While various arrangements for electromagnetic transducers have therefore been heretofore suggested and/or utilized, such transducers have not been found to be completely successful for at least some uses, including providing a lightweight transducer that is capable of providing high power.
In particular, the prior art does not teach the necessity to disperse the conductors to enable high speed operation, due, at least in part, to a widely taught theory that the magnetic field is very low in the conductors. With conductors built according to conventional teachings, however, it has been found that torque, at constant current, decreases with increasing speed, which result is contrary to the conventional expectation that torque would remain high as speed increases (which is the result achieved by this invention).